Gill is over the top with Sovereignty, he viewed the Elect justified before they came to actual faith in Christ.
Where? Belief in God's Sovereignty includes believing and obeying what God has Revealed in His Word.
This leads to several other problems related to "hyper."
There are nothing but problems with "hyper", but I don't think they could ever be 'justified' by alleging Gill led them there.*
Now, if you want to check and see where it is that he may have written about that word 'Justification', in its sense when used concerning the Perspective God has on it, such as where we see God's Perspective in the same kind of way regarding our being considered and stated as our being
"Glorified", already in His Mind, etc., in
Romans 8:30;
"Moreover whom He did Predestinate, them He also Called: and whom He Called, them He also Justified:
and whom He Justified, them He also Glorified", Gill introduces that like this;
"I have, in a former part of this work, see Body of Doctrinal Divinity, Book II,
Chapter 5: Adoption as an Immanent Act & Justification as an Immanent Act, where Justification, is threated as an Immanent and Eternal Act in God; and so it may be said to be from Eternity, and before Faith; and
in what sense Justification may be seen as an Imminent Act of God, with a removal of objections, has been shown in the place referred to, above;"
(then, below, we see Gill's belief concerning the believer's Justification, at the Time of their Salvation) "and therefore shall only now discourse concerning Justification, as it terminates in the conscience of a believer; and which the scriptures style Justification by Faith."
Here are some places Gill speaks about Justification being called, "the Righteousness of Faith", #Ro 4:13 and where Justification is when God Justifies "him that Believeth in Jesus," in Doctrinal Divinity~Book 6, Chapter 8: Justification:
(See attached doc., "Justification Gill")
"
1. The Efficient Cause of the Pardon of sin and Justification from sin, is God: as God Only can and does Forgive sin, it is His Prerogative, it is Peculiar to Him; so it is God that Justifies the sinner, and He Only;
"there is One God, Who Justifies the Circumcision by Faith, and the Uncircumcision through Faith"; that is, that
"there is One God, Who Justifies" both Jews and Gentiles,
who Believe in Christ,
#Mr 2:7 Ro 3:30."
"5b5d. Justification is called,
"the Righteousness of Faith",
#Ro 4:13 not that Faith is Righteousness, or Righteousness Imputed for Faith, or is the matter of a Justifying Righteousness, or any part of it; but because the Righteousness of Christ is Revealed by Faith, and it is the believer's Faith that lays hold onto Justification, receives Justification, and rejoices in Justification..."
"7b. It is an Act of Justice, as well as of Grace: God is Righteous in all His Ways and Works, and so in this; the Law being Perfectly Fulfilled by Christ, the Surety, both with respect to Precept and Penalty; Justice is Fully Satisfied, and so God is
"Just, and the Justifier of him that Believeth in Jesus", #Ro 3:26."
*And now, to remove this seeming difficulty, let it be observed, that the Elect of God may be considered under two different "Heads", 1.) Adam and 2.) Christ, and as related to Two Covenants at one and the same time;
1.) "as they are the Descendants of Adam, they are related to him as a Covenant Head, and as such, sinned in him, and Judgment came upon them all to Condemnation and Death, and so they are, by nature, children of Wrath, even as others.
2.) "But as considered in Christ, they are Loved with an Everlasting Love, Chosen in Him before the World was, and always Viewed and Accounted Righteous in Him, and so secured from Everlasting Wrath and Damnation;
"hence it is no contradiction to say;" again:
1.) "that the Elect of God, as in Adam, and according to the Covenant of Works, are under the Sentence of Condemnation;
2.) "and that as in Christ, and according to the Covenant of Grace, and the Secret Transactions thereof, they are Justified, and Saved from Condemnation.
"This is no more a contradiction, than that they were Loved with an Everlasting Love, and yet are children of Wrath, at one and the same time, as they most certainly are;
"nor than that Jesus Christ was the Object of His Father's Love and Wrath at the same time, He Sustaining Two Different Capacities, and Standing in Two Different Relations, when He Suffered in the Room and Stead of His people;
While, "as the Son of God He was Always the Object of God's Love; as the Surety of His people, Bearing their sins, and Suffering for them, He was the Object of God's Wrath,
as we see in
Psalm 89:38;"
"But Thou hast Cast Off and Abhorred,
Thou hast been Wroth with Thine Anointed."
In the Englishman's Concordance, the word used in the KJV called 'wroth' is hiṯ·‘ab·bar·tā — of which there is 1 Occurrence
in
Psalm 89:38;
HEB: זָ֭נַחְתָּ וַתִּמְאָ֑ס
הִ֝תְעַבַּ֗רְתָּ עִם־ מְשִׁיחֶֽךָ׃
NAS: and rejected, You have been full of
wrath against
KJV: and abhorred, thou hast been
wroth with thine anointed.
English Standard Version
But now you have cast off and rejected; you are full of
wrath against your anointed.
NASB 1995
But You have cast off and rejected, You have been full of
wrath against Your anointed.
NASB 1977
But Thou hast cast off and rejected, Thou hast been full of
wrath against Thine anointed.
Legacy Standard Bible
But You have cast off and rejected, You have been full of
wrath against Your anointed.
Amplified Bible
But [in apparent contradiction of all this] You [the faithful LORD] have cast off and rejected; You have been full of
wrath against Your anointed.
New Revised Standard Version
But now you have spurned and rejected him; you are full of
wrath against your anointed.
A Faithful Version
But You have cast off and rejected us; You have been full of
wrath against Your anointed.
etc.
That is not what the Calvinists believe that I know personally.
Let me guess, the 'Calvinists' you know are 'Reformed Baptists', or other products of the Reformation?